[arm-allstar] Motorola GM350

[Kurt Hallmeyer]

Alan,

 

I have used GM300's with decent success and they have a similar 16-pin
connector.  Here is my programming for the 16 pin connnector on the radio.

2              Tx audio (Mic audio)

3              PTT (Ground to Tx)

4              CSQ Det                               Active High

6              Channel Select 1               Active Low

7              Ground

8              Channel Select 2               Active Low

9              Channel Select 3               Active Low

11           Rx audio

12           Channel Select 4               Active Low

14           PL/DPL + CSQ Det            Active Low

 

If I recall (this is from memory so.) the CSQ on Pin 4 can only be used
active high due to the way it is designed in the radio (at least for GM300,
not sure about 350).  Setting it to Low will not work correctly on a GM300.
If you need active low there are other pins that can be programmed to
support COS active low, just not pin 4 as I recall.  If you use PL
(recommended) then you need a jumper in the front mic socket (pin 3 to 4) to
simulate a mic hangup box grounding the hook switch to enable PL.  

 

On a GM300 you can also use aux pin 5 on the rear connector to inject flat
Tx audio as an option to using the mic Pin #2.  I use the mic pin 2 with a
10uF non-polar electrolytic in series to block DC and pass audio.  You could
use a polarized cap with plus toward the radio.  A cap may not even be
necessary depending on your FOB as some of them have that built in.

 

Kurt KK7WK